An army officer came out as transgender after "living an act" as a man serving on the frontline in Afghanistan.

The British Army's first transgender officer was born a boy and decided to become a woman after a tour of duty.

Captain Hannah Winterbourne of the Royal Electrical Mechanical Engineers told The Sun she realised her "body was wrong" at the age of 23 while at Sandhurst for officer training.

The 27-year-old feared what the reaction would be and praised the military for being "very forward thinking".

She said: "I was living an act.

"I was acting for everyone around me. There was no let up where I could not stop that act.

"In my part of the tent there were seven guys living on top of each other. Previously I'd relished my own time where I could be honest with myself.

"In Afghanistan I could not do that. So that was a nudge which eventually ended up with me coming out and changing myself and my way of life."

While Capt Winterbourne, who did not reveal her former name as a man, said her feelings about her gender started from a young age, it was not until much later she decided to go through with the transformation and begin hormone therapy.

She told the Sun: "Society says to you that young boys play with trucks and wear blue and I just never really fell into that category. As I got older those feelings became more solidified, then around the age of puberty you begin to understand a little more about gender.

"That's when I thought "this is wrong for me, I'm actually female."

She added: "The point where I realised I was a woman but my body was wrong was around age 23 at Sandhurst. But I wrongly thought I couldn't do anything about it," she said.

"Then I went to my first unit. All of a sudden I've got soldiers under my command. I thought, 'This isn't the time to do it, I'll just bear with it'. But those feelings never go away."

Determined to have a career in the army, Hannah enrolled at a residential college designed for students to enter the Forces.

The Army sponsored her Electronic Engineering degree at Newcastle University. From there she went on to Sandhurst.

She was then posted to Germany. It was here that she asked doctors to begin the transition process.

Hannah is now living openly as a woman - one year on from the full transformation after beginning hormone therapy.

She said: "You don't know how the world is going to react. The fear sits on top of you and buries you. It is hard to claw your way out of it.

"By going through hormone therapy and some surgery they have allowed me to change my body to an extent where I can feel happy enough to walk down the street as a female.

"People see a female and they interact with me as a female. It has given me self-confidence."

The military has won several equality accolades in recent times, including last year being named the world's second most gay friendly military in the world by a think-tank, while the MoD won the most improved employer award in Stonewall's Workplace Equality Index